Protection of phosphorus



g No Drawing.

Patented Oct. 4, 193.2

WILLIAM H. WAGGAMAN, or LAKELAND, STAPLETON D. GOOCI-I, or LAKE wALEs, AND

FRIEDRICH P. KEBSCHBAUM, or WINTER HAVEN, FLORIDA, ASSIGNORS TO CORONE'I' PEOS PHATE COMPANY, or new YORK, N. Y., A oonronarron or NEW YORK PROTECTION OF PHOSPHORUS a non-oxidizable layer or coating so as to.

eliminate the danger of oxidation of the phosphorus and to facilitate handling and shipping.

'Anotherobject is to treat phosphorus so as to permit the recharging of impure phosphorus sludge-to a furnace without danger of 2 loss so that the element may be revolatilized.

Yet another object is to provide as an artlcle-of manufacture a protected phosphorus wvliicli can immediately be used in the production of phosphorus alloys.

Yet another object is to provide as an article of commerce relatively non-oxidizable phosphorus.

With these and other equally important objects in view, the invention comprehends the concept-of coating the phosphorus, either in the pure or impure form, with a relatively non-oxidiza'ble coating. In the preferred form of the invention the material of the coating is so chosen as to permit the coated T product to be used directly for the desired purposes Without removal of the protective coating.

It will be appreciated that with the given concept in mind a variety of methods may beemployed to achieve the improved results.

In one preferred form the phosphorus, either as elemental pure phosphorus cakes or as lumps'of phosphorus sludge, is treated with a solution of a salt of a readily reducible compound and thereafter precipitating upon the cakes or lumps of phosphorus either a phosphide or the reduced element of the compound, or a mixture of the phosphide and the element. For example, the beneficial results herein described may be obtained by treating lumps of phosphorus, at ordinary temperatures, with a dilute solution of a copper salt, such for example as copper sulphate. The amount of the salt need only be sufiicient to insure the final protective coat. In such Application filed February 27, 1931. Serial No. 518,888.

circumstances the quantity of salt employed in the solution equals approximately 2% of the weight of the phosphorus coated. In these circumstances a coating of copper and/or copper phosphid-e is precipitated upon the cake or lump of the phosphorus and renders the phosphorus substantially non-oxidizable, for it may be exposed to air with practically no danger of combustion.

In lieu ofutilizing a solution of a copper salt, other salts of a readily reducible compound, such as tin or zinc, may be employed. It is to be noted that with these materials a secondary function is subserved when the phosphorus is to be employed in the manufacture of phosphorus alloys such as phosphor-bronzes. The copper, tin or zinc, either in metallic form or as a phosphide compound, not only serves as a protective coating for the phosphorus, but also serves as one of the components of the alloy. Hence the phosphorus in this form may be immediately added to the melt without any preliminary removal of the protective coating.

While the use of compounds of copper, tin and the like in the form of protective coatings is particularly useful when the final article is'to be employed in the manufactureof alloys, it will be apprcciated'that theinvention is not restricted to the use of these materials, for the major protective function may be insured by utilizing solutions of other readily reducible metallic compounds.

Also it is to be observed that the concept of the inventionresides broadly in the production, as an article of manufacture, of a protected phosphorus particle. Therefore, other methods of applying theprotective coat ing maybe employed. For example, instead of precipitating the protective medium from a solution, thisprotective medium may be first made up and .then applied to the phosphorus by means of an aqueous suspension. Thus, instead of forming the copper or tin phosphide in situ and on the surface of the'ph-osphorus, this compound may first be made up and then suspended in a body of water from which it is allowed to settle or precipitate out upon the surface of the phosphorus particle.

.It will be understoodalso thatthe application of the protective coating may be efi ected at any. desired stage in the'manufacture of the phosphorus. As noted hereinbefore, the use of the present protective metl1od'presents decided advantages when employed during the manufacture of the phosphorus. For

elemental "crude phosphorus, produced for example by the electricor blast furnace meth od, may be providedwith a protective coat ing and then recharged to the furnaceto be revolatilized to obtain phosphorus in a puresuitable ingredients. In lieu of the coatings of the insoluble" and'non-oxidizable cupric phosphide and stanic phosphate, the coating may comprise amixture of these two or other protective'compounds and/or a mixture of protective metals. Therefore,- the'invention is considered to reside broadly in the idea of providing phosphorus either in the pure or relatively impure form with a sing said phosphorus in a solution of a protective coating so. as to render the phosphorus in fact substantially non-'oxidizable.

1. A process for protecting phosphorus against oxidation comprising treating said phosphorus with a solution of a readily reducible compound and precipitating thereon a protective surface of a non-inflammable substance. I

2. A process for producing non-inflammable lumps and cakes of phosphorus comprising immersing said lumps and cakes in solutions of readily reduciblefcompounds and precipitating on said phosphorus coatings which prevent contact of the air or oxygen with the phosphorus.

3. A process for rendering yellow phosphorus non-inflammable comprising immer sing said phosphorus in a solution of a readily reducible rompound and precipitating on the surface or the phosphorus a relatively non-- oxidizable coating. l I

4. A process for protecting crude phosphorus against oxidation comprising immerreadil reducible com ound and reci itatin thereon-a coating which prevents ready contact of air or oxygen with the crude phosphorus. r I

5. A process for protectingphosphorus against oxidation comprising immersing the phosphorus in a solution of the metallic salt ph osphide of the metal.

phide of copper.

and precipitating thereon a coating of the" 6. A process for protecting phosphorus against oxidation comprising treating said phosphorus with a solution of a copper salt and precipitating thereon a coating of phos- '7. A process against oxidation comprising treating the phosphorus with a solution of a copper salt and precipitating thereon metallic copper. 8. A process forprotecting phosphorus against oxidation comprising treating the phosphorus with a solution of a copper salt and precipitating thereona coating comprising a mixtureof metallic copper and'copper phosphide.

9. A process i 'or protecting crude phosphor.- us against oxidation comprising treating it with asolution of atin salt and'precipitatmg thereon a relatively non-oxidizable coating of phosphide-of tin." i V 10. A process for protecting phosphorus against oxidation comprising immersing it in a solution of tin salt'precipitating thereon a relatively non-oxidizable coating of metal lic tin.- r y 11. A process for protecting phosphorus against oxidation comprising treating it with a soiutioniot a tin salt and precipitating thereon a mixture of metallic tin and phosphide oftinf r V 1 12. As an article of commerce, a unitmass of phosphorus having an exposed surface comprising a metal "phosphide i 13. As an article of commerce; a unit'mass of phosphorus having an exposed surface comprising a mixture of a 'phosphide and a metal precipitated thereon. f I '1 j 14. Asian article of commerce, a unit mass of phosphorus having an exposed surface comprising metal precipitated thereon.

.15. As an article of commerce, a unit mass 7 a. .70 for protecting phosphorus. i

of phosphoruathe exposed surface of which 1 of alloying I tures. V

[WILLIAM H. WAGGA-MAN FRIEDRICH P. KERscHBAUM,

'STAPLETON-D.GUOOOH-, f 

